Adding upstream version 3.2.1+dfsg.upstream/3.2.1+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 159 insertions, 0 deletions

diff --git a/raddb/mods-config/sql/ippool-dhcp/mssql/procedure.sql b/raddb/mods-config/sql/ippool-dhcp/mssql/procedure.sql
new file mode 100644
index 0000000..4cfbe1c
--- /dev/null
+++ b/raddb/mods-config/sql/ippool-dhcp/mssql/procedure.sql
@@ -0,0 +1,159 @@
+--
+-- A stored procedure to reallocate a user's previous address, otherwise
+-- provide a free address.
+--
+-- Using this SP reduces the usual set dialogue of queries to a single
+-- query:
+--
+--   BEGIN TRAN; "SELECT FOR UPDATE"; UPDATE; COMMIT TRAN;  ->  EXEC sp
+--
+-- The stored procedure is executed on an database instance within a single
+-- round trip which often leads to reduced deadlocking and significant
+-- performance improvements especially on multi-master clusters, perhaps even
+-- by an order of magnitude or more.
+--
+-- To use this stored procedure the corresponding queries.conf statements must
+-- be configured as follows:
+--
+-- allocate_begin = ""
+-- allocate_find = "\
+--      EXEC fr_dhcp_allocate_previous_or_new_framedipaddress \
+--              @v_pool_name = '%{control:${pool_name}}', \
+--              @v_gateway = '%{DHCP-Gateway-IP-Address}', \
+--              @v_pool_key = '${pool_key}', \
+--              @v_lease_duration = ${lease_duration}, \
+--              @v_requested_address = '%{%{${req_attribute_name}}:-0.0.0.0}' \
+--      "
+-- allocate_update = ""
+-- allocate_commit = ""
+--
+
+CREATE OR ALTER PROCEDURE fr_dhcp_allocate_previous_or_new_framedipaddress
+	@v_pool_name VARCHAR(64),
+	@v_gateway VARCHAR(15),
+	@v_pool_key VARCHAR(64),
+	@v_lease_duration INT,
+	@v_requested_address VARCHAR(15)
+AS
+	BEGIN
+
+		-- MS SQL lacks a "SELECT FOR UPDATE" statement, and its table
+		-- hints do not provide a direct means to implement the row-level
+		-- read lock needed to guarentee that concurrent queries do not
+		-- select the same Framed-IP-Address for allocation to distinct
+		-- users.
+		--
+		-- The "WITH cte AS ( SELECT ... ) UPDATE cte ... OUTPUT INTO"
+		-- patterns in this procedure body compensate by wrapping
+		-- the SELECT in a synthetic UPDATE which locks the row.
+
+		DECLARE @r_address_tab TABLE(id VARCHAR(15));
+		DECLARE @r_address VARCHAR(15);
+
+		BEGIN TRAN;
+
+		-- Reissue an existing IP address lease when re-authenticating a session
+		--
+		WITH cte AS (
+			SELECT TOP(1) FramedIPAddress
+			FROM dhcpippool WITH (rowlock, readpast)
+			JOIN dhcpstatus
+			ON dhcpstatus.status_id = dhcpippool.status_id
+			WHERE pool_name = @v_pool_name
+				AND expiry_time > CURRENT_TIMESTAMP
+				AND pool_key = @v_pool_key
+				AND dhcpstatus.status IN ('dynamic', 'static')
+		)
+		UPDATE cte
+		SET FramedIPAddress = FramedIPAddress
+		OUTPUT INSERTED.FramedIPAddress INTO @r_address_tab;
+		SELECT @r_address = id FROM @r_address_tab;
+
+		-- Reissue an user's previous IP address, provided that the lease is
+		-- available (i.e. enable sticky IPs)
+		--
+		-- When using this SELECT you should delete the one above. You must also
+		-- set allocate_clear = "" in queries.conf to persist the associations
+		-- for expired leases.
+		--
+		-- WITH cte AS (
+		-- 	SELECT TOP(1) FramedIPAddress
+		-- 	FROM dhcpippool WITH (rowlock, readpast)
+		--	JOIN dhcpstatus
+		--	ON dhcpstatus.status_id = dhcpippool.status_id
+		-- 	WHERE pool_name = @v_pool_name
+		-- 		AND pool_key = @v_pool_key
+		--		AND dhcpstatus.status IN ('dynamic', 'static')
+		-- )
+		-- UPDATE cte
+		-- SET FramedIPAddress = FramedIPAddress
+		-- OUTPUT INSERTED.FramedIPAddress INTO @r_address_tab;
+		-- SELECT @r_address = id FROM @r_address_tab;
+
+		-- Issue the requested IP address if it is available
+		--
+		IF @r_address IS NULL AND @v_requested_address <> '0.0.0.0'
+		BEGIN
+			WITH cte AS (
+				SELECT TOP(1) FramedIPAddress
+				FROM dhcpippool WITH (rowlock, readpast)
+				JOIN dhcpstatus
+				ON dhcpstatus.status_id = dhcpippool.status_id
+				WHERE pool_name = @v_pool_name
+					AND framedipaddress = @v_requested_address
+					AND dhcpstatus.status = 'dynamic'
+					AND ( pool_key = @v_pool_name OR expiry_time < CURRENT_TIMESTAMP )
+			)
+			UPDATE cte
+			SET FramedIPAddress = FramedIPAddress
+			OUTPUT INSERTED.FramedIPAddress INTO @r_address_tab;
+			SELECT @r_address = id FROM @r_address_tab;
+		END
+
+		-- If we didn't reallocate a previous address then pick the least
+		-- recently used address from the pool which maximises the likelihood
+		-- of re-assigning the other addresses to their recent user
+		--
+		IF @r_address IS NULL
+		BEGIN
+			WITH cte AS (
+				SELECT TOP(1) FramedIPAddress
+				FROM dhcpippool WITH (rowlock, readpast)
+				JOIN dhcpstatus
+				ON dhcpstatus.status_id = dhcpippool.status_id
+				WHERE pool_name = @v_pool_name
+					AND expiry_time < CURRENT_TIMESTAMP
+					AND dhcpstatus.status = 'dynamic'
+				ORDER BY
+					expiry_time
+			)
+			UPDATE cte
+			SET FramedIPAddress = FramedIPAddress
+			OUTPUT INSERTED.FramedIPAddress INTO @r_address_tab;
+			SELECT @r_address = id FROM @r_address_tab;
+		END
+
+		-- Return nothing if we failed to allocated an address
+		--
+		IF @r_address IS NULL
+		BEGIN
+			COMMIT TRAN;
+			RETURN;
+		END
+
+		-- Update the pool having allocated an IP address
+		--
+		UPDATE dhcpippool
+		SET
+			gateway = @v_gateway,
+			pool_key = @v_pool_key,
+			expiry_time = DATEADD(SECOND,@v_lease_duration,CURRENT_TIMESTAMP)
+		WHERE framedipaddress = @r_address;
+
+		COMMIT TRAN;
+
+		-- Return the address that we allocated
+		SELECT @r_address;
+
+	END
+GO